The present invention relates to a method, apparatus and product relating to fibrous mat and more particularly to a unique and novel arrangement for making fibrous mat in such a combined manner that the resulting attenuated fibrous layered mat has fiber layers, each of select fiber size distribution and, if elected a controlled surface and variable permeability.
The present invention has particular applicability to polymer fibrous mat produced by melt blowing die apparatus but it is to be understood that the present invention can be readily utilized in layered mat production where in layered fibrous mats of other fibrous materials in addition to preselected polymer material—such as glass—are extracted in die attenuated form from heated die sources unto spaced collector sources.
Layered fibrous mat composed of fibers attenuated from a heated die source unto a space layered matt collector surface are generally well known in both the glass and melt blown arts but none have utilized the unique and novel unified arrangement disclosed herein. Although, as above-noted, the present invention is not be considered as limited to die feeding polymer materials from heated melt blown die sources, the unique and novel arrangement set forth herein has particular applicability in the melt blowing die feeding arrangements as disclosed in the U.S. Pat. No. 5,725,812, issued to Kyung-Ju Choi on Mar. 10, 1998; U.S. Pat. No. 5,891,482, issued to Kyung-Ju Choi on Apr. 6, 1999; U.S. Pat. No. 5,976,209, issued to Kyung-Ju Choi on Nov. 2, 1999; U.S. Pat. No. 5,976,427, issued to Kyung-Ju Choi, also on Nov. 2, 1999; U.S. Pat. No. 6,159,318, issued to Kyung-Ju Choi on Dec. 12, 2000; and U.S. Pat. No. 6,230,776, issued to Kyung-Ju Choi on May 15, 2001.
The external treatment of fibers with respect to a fiber collecting source is generally well known in the production of non-woven fabrics, attention being directed to U.S. Pat. No. 4,095,312, issued to D. J. Haley on Jun. 20, 1978, wherein fibers are collected from two fiber feeding sources to a pair of moving collecting surfaces to form a nip; to U.S. Pat. No. 4,100,324, issued to R. A. Anderson, et al. on Jul. 11, 1978, wherein wood pulp fibers are added to a matrix of collected polymeric melt blown microfibers; to U.S. Pat. No. 4,267,002, issued to C. H. Sloan on May 21, 1981, wherein fibers are formed in elongated rod shape with a heavy build-up in a central portion and a light build-up in a lip portion folded back over the central portion; to U.S. Pat. No. 4,375,446, issued to S. Fujii, et al. on Mar. 1, 1983, wherein melt blown fibers are collected in a valley-like fiber-collecting zone formed by relatively moveable and compressible porous plates which have a controlled number of pores; and, finally to U.S. Pat. No. 4,526,733, issued to J. C. Lau on Jul. 2, 1955, wherein a fluid stream of attenuated fibers is preselectively temperature treated upon exiting die tip orifices to provide improved collected web properties.
Although these above-noted patents disclose various external treatments of fiber streams attenuated from heated die sources, none teaches or suggests, either alone or in combination, the economical and straight-forward arrangement which includes successively feeding and combining fiber layers, each layer having select fiber size distributions and, if elected, the novel diversion and vortically creating force exertion of a selected portion of fiber streams to provide fiber layers with select fiber size distributions, selected surface, and, selected variable permeability of the total fibrous mat as it passes to a fiber collecting source.
The present invention provides a unique and novel die attenuated fiber arrangement including a straight-forward, economical and inventively unified production method, apparatus and final layered, relatively strong fibrous mat product which allows for efficient and economic control of fiber size distribution, surface, and permeability of a layered fibrous mat product which can have selected fiber size distributions, variable density, permeability and surface.
The present invention accomplishes the unique features thereof with a minimum of apparatus, parts, elements, and method steps in both manufacture and maintenance and, at the same time, which allows for ready adjustment to control variable fiber mat density, fiber distribution, mat permeability and surface in selected areas of a produced fibrous mat.
Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.